Fox-7

This is just an idea for a procedure to make the energetic compound, Fox-7, using readily obtainable precursors.

(1) oxidize ethylene glycol to glycolaldehyde
(the glycolaldehyde does not need to be separated from the unreacted ethylene glycol)
Glycolaldehyde is also common and easily obtainable from chemical supplies, if you find the oxidation procedure to be too messy of inconvenient.

(2) reflux the glycolaldehyde with ammonia solution and acetic acid. This will form 2-methyl imidazole.

A similar condensation cyclisation was already been described in the literature: "Imidazoles from ammoniacal solutions of glycolaldehyde and hydroxypyruvaldehyde" M.R. Grimmett and E.L. Richards

(3) Perform a nitration on the 2-methyl imidazole using mixed acids. This should yield 2-dinitromethyl-4,5-dinitro imidazole.

(4) Dilute with water and separate out the nitrated product.
Then react with concentrated ammonium hydroxide. The 2-dinitromethyl-4,5-dinitro imidazole will hydrolyse into [b]Fox-7[/b], ammonium nitrite, and the condensation product of acetaldehyde and ammonia.

(The acetaldehyde-ammonia byproduct could be saved, and may be useful for other future reactions, for example to prepare 1,2,4-triazine.)

So basically, the only precursors needed would be:
anti-freeze
KMnO4
white vinegar
98%conc H2SO4
KNO3 or 70%conc HNO3
household cleaning ammonia

What do you think? Any comments? Obviously it has not been tested, but it seems relatively straightforward.
 
 
Using Fox-7 as a Precursor for Much More Powerful Compound

http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=cv4p0074
states that the reaction of 2-nitroaniline with hypochlorite solution produces "benzofurazan oxide" (more commonly named benzofuroxan).

Could the explosive "Fox-7" be similarly converted (by reaction with NaOCl) to 3-amino-4-nitro furoxan?
The actual chemical name for Fox-7 is 1,1-diamino-2,2-dinitroethylene.

Would further oxidation by the hypochlorite bridge the two amino groups, to yield 4,4’-Dinitro-3,3’-diazenofuroxan (DDF)?
Edit Note- picture is currently link, needs to be saved as picture

If this route is feasible, it could potentially be a very direct and convenient way to prepare DDF, since the commercial availability of Fox-7 is increasing as a specialty research propellent. A few members in this forum have actually prepared Fox-7.

DDF molecular structure:
NO2-(C2N2O2)-N=N-(C2N2O4)-NO2,
where (C2N2O4) represents a furoxan ring.


Wikipedia describes DDF as having an extremely high detonation velocity around 10,000 m/sec, with a density of
2.02 g/cm3.

From another source (translated from russian literature):
Dinitroazofuroxan (formula C4N8O8 ) is thermally unstable, has a detonation pressure of 460kbar, and a detonation velocity of 9.7 km/sec at 1.94 g/cm3. The compound was fairly sensitive, but not extremely so.
"Dinitroazofuroxan" is just another simplified name for the 4,4’-Dinitro-3,3’-diazenofuroxan (DDF).

 

Having actually seen the the original reference, the 10,000 m/sec detonation velocity that wikipedia states for DDF is certainly not a precise measurement or calculation.

It is quite possible that the crystal density of the compound is actually 2.02 g/cm3, as wikipedia states. Sometimes, in these sorts of situations, there exist more than one measured density value for the same compound in the literature. Usually the larger value is correct, as often the substance being measured was not in its most compact form. One really cannot blame researchers for not wanting to work with a big sample size, then boil out all the solvent and squeeze it down to get rid of potential little air bubbles, when the substance could likely explode! Another problem is that some of these energetic compounds have thermal stability problems. Trying to melt it down or boil out all traces of solvent is likely to cause some minor decomposition, which will upset the results.

Assuming that DDF actually has a 9.7 km/sec at a density of 1.94 g/cm3, and assuming its actual crystal density is 2.02 g/cm3, a calculation can be made.

√(9.7^2 * 2.02/1.94 ) = 9.89797959

that is to say that the square of 9.7 times 2.02, divided by 1.94 is 97.97. then the square root of that is 9.89797959.
you might wonder why the 9.7 was squared, and then the square root was later taken. This is because energy is proportional to the square of velocity, the relationship is not linear. 9.7 * 2.02/1.94 would actually have given an even higher value of 10.1.

If the values quoted in the literature from both sources are correct, which is a big assumption, then DDF actually has a detonation velocity of about 9,898 meters per second, in its densest form. Remember, this value should not be taken as a precise calculation, but rather as an indicative estimate.

These sorts of calculations can be used to help fill in gaps in knowledge about obscure explosives, for which there is little available research. Please feel free to share your own comments or opinions about this calculation


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